The present invention relates to a vehicle occupant restraining system, in particular to a vehicle crash-safety seat for an occupant (driver or passenger) which has a deploying air bag mounted in the seat bottom and adapted to shoot upward out of the seat bottom when the deploying air bag is inflated during a vehicle collision.
Starting in model year 1999, the federal government required automakers to install driver and passenger air bags for frontal protection in all cars, light trucks, and vans. Still, about 30,000 occupants die in crashes on U.S. roads each year. Most of these people die in frontal crashes.
An air bag is a large inflatable bag placed inside the steering wheel and inside the dashboard. When sensors placed around vehicle detect a collision, they trigger off the air bags to inflate. This is supposed to happen at vehicle speeds above 10-15 mph. The rapid inflation is made possible by a small canister of sodium azide that releases nitrogen gas and sodium hydroxide dust. This chemical reaction causes the air bag to inflate with over 1000 pounds of pressure, there is a lot of force. During this inflation, the canister heats up to about 300 degrees of temperature. To aid in a smooth release, the air bag is coated with either talc or corn starch.
For reducing a chance of injury in a crash, all occupants, sitting in vehicles, should be properly restrained, regardless of size. All front seat passengers (adults and children) should move the seat as far rearward as possible, and may tilt the seat back slightly to help maximize the distance between the passenger's chest and the instrument panel. In order to allow the air bag to deploy safely, front seat passengers should avoid leaning or reaching forward, keeping the arms away from the area in which the air bag will deploy, and should remain seated against the vehicle seat back, with as little slack in the belt as possible to minimize forward movement in a crash.
Air bags inflate with great force. If occupants unrestrained, leaning forward, sitting side ways or out of position in any way, they are at greater risk of injury or death in a crash and may also receive serious or fatal injuries from the air bag if driver or passenger is up against it when it inflates.
A big risk of serious or fatal injury offer current air bags to identifiable groups of people, for example, people who cannot avoid sitting extremely close to air bags, people with certain medical conditions, elderly people, and young children.
Some number of people may still be at risk because they will be more likely than the general population to be too close to their air bags.
When the steering wheel and the dashboard air bags inflate, a fairly loud noise may be heard, followed by release of smoke. This smoke is actually powder from the airbag's surface. The smoke may cause irritation and choking. Those with a history of breathing trouble should get fresh air promptly.
Air bags had caused the death of many occupants in low speed crashes. All crashes in which children were killed due to impacts from the air bag.
National Highway Traffic Safety Administration (NHTSA) issued a final rule requiring that all new cars have labels placed conspicuously in order to alert occupants to the dangers of placing children in the front seat of vehicles with air bags.
The energy required to inflate air bags can injure occupants on top of, or very close to, air bags as they begin to inflate. In the first few milliseconds of inflation, the forces can seriously injure anyone struck by an inflating air bag. Serious inflation injuries occur because of occupants' positions when the air bags begin inflating. Anyone on top of, or very close to, an air bag as it begins to inflate is at risk. This is why most air bag deaths involve occupants who were positioned improperly. Other occupants at risk include drivers who sit or who lean forward in their seats, so they are very close to the steering wheel, infants in rear-facing restrains, and small children, positioned in front of passenger air bags.
The Insurance Institute for Highway Safety estimates that air bags cause injuries 42 percent of the time they deploy. The more serious injuries range from broken arms and ribs to torn heart valves and bruised lungs.
Research indicates that air bags mainly kill infants, children, short women, and the elderly. Most deaths are the result of severe injuries to the brain, spinal cord or heart.